Pci Express X4 Slot; Connector - BCM RX680R User Manual

1.5.4 PCI Express x4 slot

This motherboard supports one PCIe x4 slot that complies with the PCIe x4 specifications.
1.5.5 M.2 connectors
Support PCIe, SATA and USB interface of this connector.
RX680R User's Manual
PCIE_X4_Slot2:
Gen 3 PCIe x4 Open Ended
M2M1:
M.2 2242/2280/22110 M Key NVMe
(Gen4 PCIe x4 + SATA III)
M2M :
M.2 2242/2280/22110 M Key NVMe
(Gen3 PCIe x4 + SATA III)
M2E :
1 x M.2 2230 E Key with CNVi Support
(PCIe x 1 + USB 2.0)
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